Fix symbols upload (#47669)

There were a couple of issues with the script. The first one is it was always trying to upload the entire .buil_id folder rather than individual files and the second one is that it could not find depot_tools on path.

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Author: godofredoc

ci/builders/linux_fuchsia.json

@@ -77,6 +77,7 @@
                 {
                     "name": "Upload to Symbol Server for arch: arm64",
                     "language": "python3",
+		    "contexts": ["depot_tools_on_path"],
                     "script": "flutter/tools/fuchsia/upload_to_symbol_server.py",
                     "parameters": [
                         "--symbol-dir",
@@ -162,6 +163,7 @@
                 {
                     "name": "Upload to Symbol Server for arch: x64",
                     "language": "python3",
+		    "contexts": ["depot_tools_on_path"],
                     "script": "flutter/tools/fuchsia/upload_to_symbol_server.py",
                     "parameters": [
                         "--symbol-dir",

tools/fuchsia/upload_to_symbol_server.py

@@ -39,15 +39,20 @@ def process_symbols(should_upload, symbol_dir):
   for (dirpath, dirnames, filenames) in os.walk(full_path):
     files.extend([os.path.join(dirpath, f) for f in filenames])
 
+  print('List of files to upload')
+  print('\n'.join(files))
+
   # Remove dbg_files
   files = [f for f in files if 'dbg_success' not in f]
 
   for file in files:
-    remote_path = 'gs://%s/%s' % (
-        FUCHSIA_ARTIFACTS_BUCKET_NAME, remote_filename(file)
+    remote_path = 'gs://%s/%s/%s' % (
+        FUCHSIA_ARTIFACTS_BUCKET_NAME, FUCHSIA_ARTIFACTS_DEBUG_NAMESPACE,
+        remote_filename(file)
     )
     if should_upload:
-      command = 'gsutil cp %s %s' % (full_path, remote_path)
+      gsutil = os.path.join(os.environ['DEPOT_TOOLS'], 'gsutil.py')
+      command = ['python3', gsutil, '--', 'cp', gsutil, file, remote_path]
       subprocess.check_call(command)
     else:
       print(remote_path)